Why was the land mine made?

Answer 1

From a tactical standpoint, the purpose behind a land mine is threefold:

(1) Area denial. An opponent will avoid an area known to be mine-filled, and thus, mines are very effective at preventing movement through a particular piece of terrain.

(2) As a corollary to (1), land mines are used to direct and channel enemy movements. As an opponent will seek to avoid crossing an active mine field, proper positioning of multiple mindfields will force an opponent to take a pre-determined pathway. This is very useful to force an opponent to pass through an area which can be set up for an ambush or enfilade fire.

(3) In the modern world where landmines can be instantly deployed via artillery, bombs, or rockets, dumping quantity of landmines on top of an opposing unit's position is a very effective method for completely immobilizing the unit. As the area that the opponent is occupying now suddenly is filled with mines, the unit can only move very carefully; this effectively allows for the "fixing" of an opponent, so that they cannot escape.